Replaceable lip dredge bucket



Sept. 28, 1943. CROUCH 2,330,409

REPLACEABLE LIP DREDGE BUCKET Filed Jan. 17, 1942 IN V EN TOR. Ja HIV CROUCH A TTURNEYS.

side.

Patented Sept. 28, 1943 more stars REPLACEABLE 'LIP DREDGE BUCKET John Crouch, Nato'ma; Calif. I Application January 17, 1942 ,se1-ia1 Ne. 427,153.

9 grams. (c1. a -r41 My invention relates to dredge buckets, and

particularly to an improved form of replaceable bucket lip. i

In certain locations the moving of earth inquantity is accomplished most economically by the use of an endless chain of digging buckets.

Typical of such uses is the digging out of stream beds and banks in mining operations. example is the deepening of a channel for navigation in a river. Other uses will immediately occur to those skilled in the art.

The lips which cut into the earth wear through) abrasive action, and become distorted or broken through contact with rocks or boulders... This wearing away. of the lips reduces the capacity of Another the individual buckets, and hence the outputof i the entirebucket chain, by as much the initial volume.

A number of types of replaceablecutting lips have been suggested. They are advantageous as compared with the replacement of the. entire, bucket in being much less expensive, andin enform of bucket in which these difficulties are overcome.

.: The use of renewable lips requires, first, that the lips be adequately anchored to the bucket; and next, that they be removed and replaced quickly, so that the entire dredge need only be idle for a minimum period of time. The lips must be strong enough to resist distortion and breakage, and the bucket shouldbe designed so that strains exerted on the lips will not deform it.

The usual digging buckets are roughly elliptical in cross-section as Viewed from above, with the longer elliptical axis parallel to the pivotal connections to the other buckets constitutingthe continuous chain, which is mounted on a digging ladder attached by suspension lines to and carried by a boom. Cutting action occurs along the forward edge of the buckets when the boom is moved straight ahead and also along the side portions when the boom is swung from-side to The latter method is common in dredging as 50% of gold bearing gravel. The boom is mounted on a a barge which is floated over the area to be Worked, temporarily anchored, and the boom and bucket chain swung fromone side of the stream to the other, making successive arcuate cuts. The cutwas j 500,000 ,pounds. edges and the means for attaching the lips to the ting action in such case will be'efiected bythe leading portions of the lip; 5 I

When operating in I this fashion, the liv'e loads, or force exerted by the-motors driving the continuous chain 'ofbuckets, is exerted through the bucket lips, and is' usually distributed between lJWO or three of them whichare in simultaneous contact with the earth. In hard ground, the strain on the individuallips may be substantially increased. The buckets tend to rideup over hard ground orbedr'ock instead of digging through asthey Wouldinless resistant formations. l x

. .As'the level of the digging ladder is thus raised,

itsweight will be supported partly or Wholly on the .few bucket lips in contact with the rock instead of on the suspen'sionlines. Exemplary, of

the additional strain thus efiective, in .one typical installation the -live v load, or digging resistance, was 120,000 pounds; while the dead load, or digging ladder weight transferred. from the. suspension lines to thelips in contactwith the, earth Obviously, the cutting buckets must be designed to resist both the live and dead; loads. l

The, forces actingmay be. analysed in relation to the individual bucket and lip by considering them to be resolved into components parallel and normal-to the lip cross-sectiomshownin Fig. 1.

Use'willbe madeof the reference characters ap- .plied specifically in the detailed description hereafter,,when necessary to an understanding of the The components due totheree force analysis. action of the ground against thecutting edge and parallelto, the lip section tends to upset the lip about the forward edge oftheupper rim l of the hood as a fulcrum This tenjdency'I overcomeby .properly positioning the stop lugs inside the hood.

adjacent the tangsoi the lip. If the lipwere to be rotated about the forward'upper hood edgeas a fulcrum, .the arcuate path of the terminal lip .porti ons'would pass directly through these inner v stop lugs, and so a direct resistancein compressionis ofiered to such movement;

Wh'en'the bucketrline is being propelledin a .reversedirection, as, in withdrawing it from a cut,

the fr ictional resistance is.efiective* as aforce component parallelto theli section of Fig. 1

and tending to unseat the lip ,by a'rcuate movement about the upper edge of the rim shoulders I 0 as fulcrums. The lip of my invention prevents this result by being shaped so that the arcuate through the hood seat II and the lip movement would be prevented thereby.

Certain prior art lips have tried to resist the upsetting forces by interlocking the lip ends with the hood. Such interlocking structures require complicated movements of the lip relative to the hood, or pre-stressing and deforming of the lip, for assembly. My invention permits straight line movement of the lip into position in the hood, and requires no deformation of the lip, while still securely maintaining the lip against such forces as tend to unseat it. No special assembly equipment is required in the field.

The weight of the digging ladder may be represented by components largely effective normally to the lip section of Fig. 1, tending to force the lip rearwardly in the bucket. Inthe prior art the engaging surfaces terminally of the lips have been set at angles which were not normal to the line of action, of these forcegcomponents. The result has been that the ends;of;.;th e lips tended to work on the inclined planes thus Drovided, out of proper alinement with the hood. I overcome this by making the terminal engaging surfaces substantially normal to th'eline .of

action of these forces. This position is also substantially normal to a tangent to the hood and lip outer surfaces adjacent their planes of engagement.

sisting such deterioration.

These advantages are obtained, in brief, by providing a tapered seat into which the lip is easily placed or removed. The construction enables an even more secure fit when cuttingpre'ssure is applied by so proportionir'ig the parts that upsetting forces are overcome within the structure, by making the lip and hood engaging surfaces substantially normal to the forces transmitted therebetween, and by so shapingthe lip and seat that they may be fitted togetherby a simple, straightline movement without prestressingor distorting. V

The construction which I have designed will be mor e'fully understood by reference to the drawings and description following, and to the objects of my invention, which include: providing an improved'form of replaceable bucket lip; providing a bucket lip in which stresses exerted against the cutting edge are effective to unite the lip more firmly to the bucket; affording abucket andlip joint in which the tendency to work out of alinement is eliminated; iie'utralizing 'forces tending to upset a bucket lip; providing a bucketlip which can be set 'inplace with a minimum .ofjmanipulation; providing a lip in a form whichI-can be replaced when worn out more simply than can those known in the :prior artyand eliminating the necessity for distorting or prestresslng the lip to join it to the hood. 1

These and other objects will be apparent to those skilled in the art from a study of-the TdiS- .closure following. It is'to be understood that the invention is intended to include any modifications necessary to adapt it to fulfill these aims,

and all such changes in form and structure as may be made with ordinary skill by those familiar with the field. All such variations I intend to comprehend within the scope of the appended claims.

In the drawings:

Fig. 1 is a side sectional view of a bucket and lip incorporating my invention;

Fig. 2 is a top view of the sectional bucket and lip showing of Fig. 1;

Fig. 3 is a fragmentary view in section showing the joint between one of the extremities of the bucket lip and the bucket, taken as indicated by line 3-3 of Figs. 1 and.2; and

Fig. 4 is a fragmentary section taken along line 4-4 of Figs. 1 and 2.

In Fig. 1, I have shown my invention as applied to a typical bucket i forming a part of an endless bucket chain, not shown in the drawing. Bucket i includes leading bosses 2 and trailing bosses 3', formed integrally with a body 3 or hood 5 in which the earth is carried. Hood 5 is roughly elliptical in cross-section, expanding in smooth curves from its bottom 6 to its upper rim 7. Upper rim 1 extends'around about two thirds of the outwardly flared forward side 9 of hood 5. An engaging face 8 is formed on rim 1, and rim shoulders 10 extend normally upward from rim 1 at either side of hood 5 near its rear. It will be understood that these relative terms will be used in connection with the drawing as follows: that portion adjoining the connections to the bucket chain will be called the rear, and the cutting sides of the bucket the front; the leading portion of the bucket will be referred to as the top, and the trailing portion as the bottom.

The inner surface of bucket hood 5 isfinished, as by grinding adjacent the rim 1, to form a tapering seat H for the reception of an engaging face 12 formed along the lower portion of removable lip id. The engaging face 12 tapers cooperatively with theseat, so that a snug nesting fit is obtained. Rearwardly on each side of hood 5, integrally formed stop lugs l5 project inwardly therefrom. An engaging face H5 is formed on lug l5 substantially coplanar with the rim shoulder It, 'but'extending downwardly from the hood rim 5. i

The lip M is formed in substantial continuation of the curvature of hood 5, with the cutting edge I! sharpened arid the-lipbody t8 thickened for strength. outer seatl3 is formed on lip i4, engaging face "8 on rim I. The life terminates at each end in an inwardly flared portion T9 of which a part is cut away, leaving a tangiil'offsetinwardly by the thickness of hood 5 to form outer lip shoulder '21. Th'e o fist 2 i engages rim shoulder l0, transmitting "stresses applied through the lip normal to the lip section of Fig. 1 directly to the hobd s. Immediately beneath the tan'g'ZQ, which is inin'timate Contact with the innersurface of the hoo'd 5;, thatpart of theinwardly flared'lip portion l9 'whichwas cut away forms engaging surface, or inner lip shoulder 24, butting against the engaging surface ffi'of stop lu'gib. Terminal -rivets25sec ure tangs 2c to hood '5, while additional inten'neiai- 'ate rivets '12:".- extending through hood 5 immediately below rim 'ij-and throughjthe lower portion 2'! of lip 'l hjointh'e hood and-lip togetheras an operative 'unit. 'I prefer that the rivets 25 and beyond the outer surface of the bucket. Ob-

; carefully manipulated.

viouslyphowever, any other suitable-arrangement could 'be'used, as rivet heads projecting both inwardly andoutwardly, bolts instead of rivets, or equivalent'means; 'Goingback to the construction of the rim shoulder I and the stop lug I theengaging face It is substantially parallel with the shoul-- seat II on the hood, and is kept in such alined 7 position while it is being-inserted.

The rimshoulder l0 and engaging face 16 are substantially normal to the hood rim l, as are the engaging faces I6 of stop lug l5 and 2d of the inwardly offset rim portion :19. The planes in which they lie are held parallel to the line along which the lip is moved into position referred tom the claims as the line of generation, so that as the lip nests in the hood, the engag ing surfaces near the tangs 20 meet smoothly, without requiring the lip to be twisted about or The engaging surfaces I (I and 2| and I6 and are also normal to a tangent to the surface of the hood and lip at the line of engagement or generation. This means that stresses transmitted between the lip and hood at these points Will not tend to cause relative movement between the two, as is the case where these engaging surfaces are other than normal to the stress line.

In prior art buckets these faces are commonly inclined, so that lip tends to ride upout of position, or to spread or pinch in, depending on the general design. Y I It will be apparent also on close inspection of the showing of Fig. 1, which is toscale, that the v lip M cannot be upset about the upper rim 1 of the hood 5, as the engaging face I6 of lug I5 is directly in the arcuate path 3| which inner lip shoulder 24 would have to traverse. Y

I Similarly, the upsetting of lip l4 about a ful crum formed by the upper edges of rim shoulder it andouter lip shoulder 2| is prevented by the tion thus contributes to economy in operation;

since the lips require renewingless frequently,

and canbereplaced much more rapidly when necessary. 1 What I claim is:

' '1. A dredge bucket, comprising a body member, means formed on said body member for pivotally linking said bucket into a bucket chain, a hood formed on said body member, a rim formed on said hood, an engaging face formed on said rim, a tapered seat formed within said rim, rim

wardly offset portions formedterminally of said lip; inner shoulders formed on said ofiset'porti'ons arranged to engage said lugs, and. outer shoulders arranged to engage said rim shoulders.

2. A dredge bucket, comprising a'body member, means for connecting said body memberin arranged to mate with said tapered seat, an outer seat formed'onsaid lip to engage with said en-' gaging face'formed on said rim; terminal. portions {inwardly offset from said lip, an'outer shoulder formed by said offset'portions and arranged -to mate with saidjrim shoulder, an inner shoulder formed on each of .said offset portions and arranged to mate with one'of said stop lug seating faces, a tang formed on each of said in-.

wardly offset portions arranged to nest withinsaid hood, and means for securing said lip to said hood. 3. A dredge bucket, comprising a bodymember, means for connectingfisaid body member in a-' bucket chain, a hood formed on said. body member, a rim formed on said hood, rim shoulders terminating said rim, an engaging face formed on said rim, an inner stop lug formed shoulders, a removable lip formed in substantial continuation of the curvature of said hood, a tapered lower face formed about said lip and arranged to mate with said tapered seat, an

outer seat formed on said lip to engage with said engaging face formed on said rim, terminal portions inwardly offset from said lip, an outer shoulder formed by said offset portions and arranged to mate with said rim shoulder, an inner shoulder formed on each of saidpoffset' portions and arranged to mate with one of said stop lug seating faces, a tang formed oneach of said shoulders formed terminally of said seat and substantially normal to the adjacent surface of said hood, lugs extending into said hood substantially co-planar with said shoulders, and a inwardly offset portions arranged to nest within said hood, and means for securing said lip to said hood,'said outer seat and said inner and outer lip shoulders being disposed in such man.-

her as to oppose adequately stresses encountered.

,4. In a dredge bucket, the combination of a body member, means for linking said body memher to a chain ofsaid buckets, a hood formedon said body member, a rim defined on said hood,-

,said hood, a removable lip, a, tapered portion formed on said lip and arranged to mate with said tapered rim seat, an outer seatformed'on said lip to engage with said engaging face formed on said rim, portions inwardly offset from said lip-on each side of. said hood,-an outer rim engaging surface formed by each of said offsets and arranged-to seat againstone of said rim shoulders, a tang formed by each of said offsets arranged to nest'snugly within said hood, an inner engaging face formed on each of said 01fsets and arranged toengage'one of said stop lugs, and means. to fix said lip to said hood; said outer seat and said outer rim engaging surface,

and saidrim shoulders,. and saidiinner engaging faces and said stop lugs, respectively, being arranged in suchlpositionasto oppose adequately stresses encountered between said lip and said hOOd. i'l

5. In a dredge, bucket, theccombination of a body member, means. for linkingsaid body memher to a chain 101' said buckets,.a hood formed on said .body member, a rim defined on saidhood, rim shoulders terminating; said rim, a tapered seat formed within said, rim, an' engaging face formedon said rim, stop lugsformed inwardly of-said. hood, a -removable lip, a tapered portion formed onisaid lip and, arranged to mate with said tapered rim seat, an, outer seat formed on said lip to engage with said engaging faceformed onsaid rim,.portions inwardly oifsetfrom said lip on eachside of said hood, an outerv rim engaging surface formed by. each of said offsets and arranged to seat against one of said rim shoulders, atang formed by each of said offsets arranged to nest snuglywithin said hood, an inner engagingfaceiormed on each of said ofisets. and arranged to engage one of said stop lugs, and means to fix said lip to said hood; said outer seat and said outer rim, engaging surface, and said rim shoulders, and said inner engaging faces and said stop lugs, respectively, being arranged in such position as to oppose adequately stresses. enc-ounteredbetween said lip and said hood, and said hood and lip being arranged to resist by direct compressive engagement forces tending to upset said lip from its seated position.

' 6. In a dredge bucket having a hood and a removaoieclip, means for relating said lip to said hood, comprising male, and female surfaces formed peripherally ,about said lip and within said hood; a rim face on said hood, and an outer seat on said lip, for respective engagement; inner and outer engaging surfaces terminally formed on said lip, and stop lugs and rim shoulders formed on said hood for respective engagement arrangedto permit; straight line entryrof said 1ip intosaid hood. and to present normal faces so as to oppose adequately. diggingstresses encountered. i. i

7. In a dredgebucket having a hood and a removable lip, means forrelating said lip to said hood, comprising male and female surfaces formed peripherally: about said lip and within said hood; a rim face on said hood, and an outer seat on said lip, for respective engagement; inner and outer engaging surfaces-terminally formed on said lip, and stop lugs and rim shoulders formed: on said hood for respective engagement arranged to permit straight line entry of said l-ip into said hood and'to present normal faces so as to oppose adequately digging stresses encountered, and means for securing said lip to said hood.

8; A dredge bucket, comprising a body member, means for connecting said body member in a bucket chain, a hood formed on said body memher, a rim formed on said hood, an'engaging face formed on said rirn, rim shoulders terminating said rim, an inner stop lug formed on said hood adjacent each of said. shoulders, a tapered seat formed within said rim, parallel-seating faces formed on said stop lugs and rim shoulders, a removable lip formed in substantial continuation of the curvature ofsaid hood, a tapered lower face formed about said lip and arranged to mate with said tapered seat, an outer seat formed on said lip to engage with said engaging face formed on said rim, terminal portions, inwardlyoffset from said lip, an outer shoulder formed by said ofiset portions and-arranged to mate with said rim shoulder, said lip being arranged'so that an arc centered at the upper edge of said outer shoulder and passing through the lower edge of said tapered lower lip face, centrally of said lip will extend directly through said tapered rim seat, an inner shoulder formed on each of said offset portions and arranged to mate with one of said stop lug seating faces, a, tang formed on each of said inwardlyoifset portions arranged to nest within said hood, and means for securing said lip to said hood, said inner and outerrlip shoulders being disposed so as to oppose adequately stresses encounteredl c 9. A dredge bucket, comprising a body member, means for connecting said body member in a bucket chain, a hood formed on said body member, a rim formed on said hood, an engaging face formed on said rim, rim shoulders terminating said rim, an inner stop lug formed on said hood adjacent each of said shoulders, a tapered seat formed within saidrim, parallel seating faces formed on said stop lugs and rim shoulders, a removable lip formed in substantial continuation of the curvature of said hood, a tapered lower face formed about said lip and arranged to mate with said tapered seat, an outer seat formed onsaid lip to engage with said engaging face formed, on said rim, terminal portions inwardly offset from said lip, an outer shoulder formed by said offset portions and arranged to mate with said rim shoulder, said lip being arranged sothatan are centered at the upper,

edge of said outer shoulder and passing through the lower edge of. said tapered lower lip face centrally of said lip will extenddirectly through said tapered rim seat, an inner shoulder formed on each of said oifset portions and arranged to mate with one of said stop lugfseating faces, said inner lip shoulder being so positioned that an,

arc drawn'through the lower edge thereof from the central portionof said hood upper rim as a. center will extend directly through said inner hood stop lugs, a tang, formed on each of said inwardly offset portions arranged to nest within said hood, and means for securing said lip to said hood, said outer seat and said inner and outer lip shoulders being, disposed so as tooppose adequately stresses encountered.

' JOHN CROUCH. 

